﻿// Copyright (c) Microsoft Corporation
//
// All rights reserved. 
//
// Licensed under the Apache License, Version 2.0 (the ""License""); you may not use this file 
// except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 
// THIS CODE IS PROVIDED *AS IS* BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED, INCLUDING 
// WITHOUT LIMITATION ANY IMPLIED WARRANTIES OR CONDITIONS OF TITLE, FITNESS FOR A PARTICULAR PURPOSE, MERCHANTABLITY 
// OR NON-INFRINGEMENT. 
//
// See the Apache Version 2.0 License for specific language governing permissions and limitations under the License.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Net.Http;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
using Windows.UI.Core;
using Windows.UI.Xaml;

namespace TED.WindowsAzure.Unplugged.Mobile.Extensions
{
    public static class UIDispatcher
    {
        private static CoreDispatcher _dispatcher;

        public static void Initialize()
        {
            if (Window.Current != null && Window.Current.Dispatcher != null)
            {
                _dispatcher = Window.Current.Dispatcher;
            }
        }

        public static void BeginExecute(Action action)
        {
            // ReSharper disable once CSharpWarnings::CS4014
            InnerExecute(action);
        }

        public static void Execute(Action action)
        {
            InnerExecute(action).Wait();
        }

        private static async Task InnerExecute(Action action)
        {
            if (_dispatcher == null)
            {
                action();
            }
            else if (_dispatcher.HasThreadAccess)
            {
                action();
            }
            else
            {
                await _dispatcher.RunAsync(CoreDispatcherPriority.High, () => action());
            }
        }
    }
}
